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The “phase transformation-induced coercivity mechanism” [6,7] suggests that the formation of Sm-rich phase on the surface of SmCo5 grains during slow cooling from 1120oC smoothes the grains surface, decreases the amount of reversed domains nuclei and, thus, increases Hci.
HRTEM investigations of the sintered magnets showed that, along with SmCo5 grains with a low density of defects, grains with closely packed parallel stacking faults are observed perpendicular to the hexagonal c-axis [8].
These micrographs reveal two phases characterized by the dark matrix grains and lighter intergranular phase.
This transformation improves the smoothness of the grain surface of the principal phase, eliminates regions with low magnetocrystalline anisotropy, decreases the number of reversed domains nuclei and, thus, increases the coercivity of magnets.
This transformation improves the smoothness of the grain surfaces and increases the coercivity of magnets.

The number of grids in scheme 1 and scheme 2 are 4,564,601 and 448,661 respectively.
The average grain area at the thinnest part is 1.2×105um2, and the average grain area at the thickest part is 1.32×105 um2.
The grain size does not differ greatly due to the difference in wall thickness.
However, the grain sizes are similar.
Therefore, the grain size and distribution of the entire casting is relatively uniform.

There are a number of small holes at front of main crack.
It can be seen from Fig. 3 that grains deformed slight at the edge of main crack and the parts of main crack edge are smooth, suggesting that little plastic deformation takes place before the nut cracks.
The SEM observation results show that brittle fracture takes place along grain edges in the nut.
It is also reported that the fracture of alloy is characteristic of grain-boundary when failure caused by stress corrosion[3].
The fracture surface topography of failure nut is in the mode of brittle fracture along grain edges and macro crack is nearly line and covers all surface of nut.

In a number of cases, periodic inspections of the technical condition of the components of pipeline systems exhibit cracks.
The precipitation process took place in under-surface areas, at austenite grain boundaries, and in energetically privileged regions, such as twinning planes and slip bands (Fig. 5) [7,8].
Fig. 5 The microstructure of the inner surface of the T-pipe: a) crack in a passive oxide layer, b) intensive precipitations of carbides in twinning planes and slip bands, as well as at austenite grain boundaries, c) a transcrystalline microcrack in an under-surface T-pipe area As a result of precipitation processes in the under-surface zones of the T-pipe, the effective content of chromium in the austenite grain boundaries’ area was too small for passivation.
As a result, the diffusion of carbon to the substrate in the steam-methane environment caused the precipitation of chromium carbide Cr23C6 in the area of the austenite grain boundary.
The revealed corrosion processes were destructive to the metal and, in particular, to austenite grain boundaries, by initiating the decohesion in their area, whereas thermo-mechanical loads caused the increase of cracks in the material fatigue process.

Laboratory equipment and Inspection equipment Laboratory test methods and test equipment such as shown in table 1: Table 1 Laboratory equipment production processes test equipment smelt 25kg vacuum inductance furnace forge 650kg forging hammer hot rolling Click the frame 2 rolls reversing mill scouring man-made cold rolling Single frame 2 rolls reversible cold rolling mill anneal Simulation of electrical steel continuous annealing furnace Magnetic detection AC magnetic characteristic measuring instrument MTR -1322 crystalline grain metallographic microscope ODF X-ray diffractometer RINT/2500PC The component design ideas In order to eliminate the corrugated shape defects, the phase change of slab heating and hot rolling, promote the dynamic recovery and recrystallization,the elimination of large deformation grain.
The aluminum is controlled at about 0.3% and do not change. 4）In order to make the silicon phase change during hot-rolling, eliminate the corrugated shape defects, prevent hot shortness while c and the addition of different amounts of Mn, content design in 0.28, 0.7, 0.9 and 1.05[3]. 5）S is a harmful element, the S is controlled in the 0.005% following. 6）P is at the grain boundary precipitation,and P is easy to make the steel brittle elements.When P content is too high, especially the carbon content is very low, bad cold workability product crisp.
So the P will control in the 0.02% following. 7）In order to improve the effect of inclusions and small precipitates on the grain, and improve the texture of the finished board, Sb segregation element to add a certain amount in steel[4].
Smelting component designs in table 2: Table 2 Design components Number of steel C Si Mn P S Al Sb 1 ≤0.005 1.80-2.00 1.90 0.15-0.35 0.28 ≤0.02 ≤0.005 0.25-0.40 0.30 - 2 ≤0.005 1.60-1.70 1.65 0.65-1.00 0.70 ≤0.02 ≤0.005 0.25-0.40 0.30 - 3 ≤0.005 1.60-1.70 1.65 0.65-1.00 0.90 ≤0.02 ≤0.005 0.25-0.40 0.30 - 4 ≤0.005 1.70-1.85 1.75 0.85-1.20 0.90 ≤0.02 ≤0.005 0.25-0.40 0.30 - 5 ≤0.005 1.70-1.85 1.75 0.85-1.20 1.05 ≤0.02 ≤0.005 0.25-0.40 0.30 - 6 ≤0.005 1.70-1.85 1.75 0.85-1.20 1.05 ≤0.02 ≤0.005 0.25-0.40 0.30 0.04 Test process In a 25kg vacuum induction having be furnaced smelting 6 furnace steel, the alloy steel were analyzed, as shown in table 3.
Fig.2 (a) visible, component 1 (2.024%Si+0.178%Mn) DSC as a smooth curve, indicating that the phase transition did not occur in the hot rolling, coarse grain formation of retained continuous casting;Component 2 (1.755%Si+0.728%Mn), but DSC is still smooth curve; Component 3 (1.71%Si+0.956%Mn) in Si content under the same conditions to add 0.23%Mn, DSC analysis has been shown to occur in phase transition, small peak.

a.0.6 m - 35 m segment mainly contains clay, sand and loam.It has coarse-grained sandstone and sandy conglomerate as well.It is thin interbedded occurrence.
It has thin, coarse-grained sandstone, sand mudstone and mudstone.Sandy mudstone is gray, purple, broken, vulnerable to weathering and local fissures filled with calcareous film.
And it also has sandstone, gray fine-grained sandstone and dark gray muddy each other rocks.The sandstone cumulative thickness is 15 meters accounting for 40% of the stratigraphic thickness.
The Shanxi group: P1S thickness is 56 m.It mainly contains gray sandy mudstone, gray and light gray medium-grained sandstone with small coal and big coal (2#) interbedded.The sandstone cumulative thickness is 22 meters accounting for 39% of this segment of stratigraph.
The technical characteristics of Main Shaft No.2 Serial Number Project Unit Quantity 1 Wellhead levation m +196 2 Wellbottom levation m - 471,651 3 Borehole depth m 667.651 4 Borehole diameter m 6 2.

The diffraction peaks presented by BFO100 sample were identified by JCPDS file peaks number 84-0757 [46].
The X-ray diffraction corresponding to BFO100 sample showed the presence of mono phase, however for the SFO100 sample, peaks were identified by the JCPDS file number 33-1340 [47] and found the presence of secondary phase- a-Fe2O3 peak at 33.11o (2q), identified by JCPDS file number 72-0469 [48].
As the concentration of Fe2+ ions increases the number of oxygen vacancies increase, and this in turn increases the rate of sintering, lowering the maximum densification temperature [140]. 1.5 Grain Growth in M-type Hexaferrites.
While the samples with x = 0.75 and 0.90 the highest values (82.92 ppm/°C and 87.83 ppm/°C), which are good numbers for microwave applications.
The X-ray diffraction corresponding to BFO100 sample showed that only one phase is present, however for the SFO100 sample, peaks were identified by JCPDS file number 33-1340 and also can be seen diffraction lines characteristic of the µ-Fe2O3 by the peak at 33.11°(2q), identified by JCPDS file number 72-0469.

The numbers on each bar in Fig. 2 mean the average elongation achieved for the single-step tests.
However, due to the high-temperature environment during the experiment, grain growth will occur, and the grains and slidable grain boundaries on a unit area decrease.
This is harmful to the grain boundary sliding and will cause the hardening effect of the material.
The grains become a bit larger and more discontinuous, and a larger portion of the α-phase becomes equiaxed grains when the strain reaches 100%, as shown in Fig. 6 (c) and (d).
When the strain reaches 150%, the grains continue to grow, but the recrystallization of the grains have transformed nearly all the grains into equiaxed shapes.

If the grain size is large, it is effective to decrease the friction coefficient in order to increase the cutting ability of the diamond grain.
This stage aims to produce a proper protrusion of grain cutting edge.
The grid size of the cast iron bonded diamond wheel is #400 (average grain size:50Ǵm) or #4000 (average grain size:4.06Ǵm).
Sliding velocity was 4mm/s, sliding stroke was 10mm and number of repeat passage was 200.
Fig. 8 The model for the abrasive grain W F Disk specimen (#400, #4000) Pin specimen A layer of oxide with a larger flexibility and low retention � � � � vertical angle � � attack angle (a) Abrasive asperity for #400 diamond grain R ǩ (b) Abrasive asperity for #4000 diamond grain (4) If grain size is large, it is effective to decrease friction coefficient in order to increase cutting ability of diamond grain.

Shur Government scientific centre of Russian Federation Public Joint-Stock Company “Research-and-Production Alliance “Central Research Institute for Machine-Building Technology” (PJSC RPA “CNIITMASH”), 4 Sharikopodshipnikovskaya street, Moscow, 115088 Russia aanna-petelina@yandex.ru Keywords: thermal aging, mechanical properties, impact strength, statistical treatment, diffusion, grain boundaries, carbide particles.
(4) The number of degrees of freedom, in this case, determined from the expression 1/к = с2/(n1 – 1) + (1 – c)2/(n2 – 1), (5) where с = (S12/n1) / (S12/n1 + S22/n2)
It can be assumed that the nucleation of new precipitates occurs on the dislocations in the places of their high density (within grains), or at the grain boundaries. 
At the same time, the average size of carbide particles in the grain boundaries initially decreases from (191 ± 9) ´ 10-3 µm before ageing to (107 ± 4) ´ 10-3 µm after ageing (3000 hours at 350 °C) and then increases again to (133 ± 7) ´ 10-3 µm with increase of the aging time up to 10000 hours. 
Consequently, the TA mechanism is associated with the grain boundary embrittlement along the carbide particles [7].